Leer



u Nov. 4. |924.

H. K. HITCHCOCK n f n LEER kF led Aug. 9

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H. K. HITCHCOCK LEER 5k Sheets-Sheet 4 FIEiF#l Nov. 4 i924. 1,514,385

. H. K. HITCHCOCK LEER Filed Aug. 9 1921 5 sheets-sheet 5 /NVENTR Patented Nov. 4, 1924.

UNITED STATES PATENT OFFICE. t

HALBHRT x. HITCHCOCK, or PITTSBURGH, PENNSYLVANIA, AssIGNoR or ONE-HALF To HITCHCOCK EXPEHIMENT COMPANY, n CORPORATION oFfNnW JERSEY.

LEER.

. Application'led August 9, 1921. Serial No. 490,836.

To ali whom t may concern: l

Be it known that I, HALBERT K.VHITCH COCK, a citizen of the UnitedV States, and a resident of Pittsburgh, in the vcounty of Allegheny and State of Pennsylvania, have made a new and useful invention -in Improvements -in Leers, of which the following 'is a speciiication.

`for.` One embodiment of the invention is illustrated inthe accompanying drawings, wherein:

Figure 1 is a lfront elevation of the leer, with apart of the supporting frame work in section; Fig. 2 is a similar side elevation of the leer; Fig. 3 is a partial secti'on and partial side elevation of one portion of the leer, the upper half of the figure being a section on the line III-III vof Fig. 4

andthe lower halfbeing a side elevation;

Fig. 4 is a vertical section on the line IV-IV of Fig. 3; Fig. 5 is a partial horizontal sec-v tion on the line V-V of Fig. 4; Fig. 6 is is an enlargedV detailed section taken at the edge of one of the drawing rolls; and Fig. 7 is an enlarged plan view of one of the vstrands of asbestos cord used upon the drawing pulleys.

kReferring to the general arrangement shown in Figs. 1 and 2, the framework for supporting the vertical leer Casing comprises the four upright corner channels 1, the main .'horizontalchannels 2 arranged in four sets at different levels and the diagonal braces 3.

` At thejcenter ofthis framework is the leer casing in the form of a vertical box, rectan ular in cross section, located above and in a ignment with the slot member 4, located inthe molten bath,such. slotmember being shown in dotted lines, although it will be understood that the .character of themolten bath from which the glass is drawn is immaterial in so far as the leer construction of the present invention is concerned. The casing 1s divided vertically into a plurality of separate compartments 5, 6, 7, 8,9, 10, l1, 12 and 13 by the inclined pairs of diaphragm walls 14. These diaphragm walls are constructed as indicated in Fig. 3, comprising a sheet metal member 15, and plate 16, and an intermediate asbestos packing 17., the upper ends of the walls terminating short of the center line of the leer and being provided at this point with a construction for permitting the passage of the sheet and yet at the same time making a comparatively tight joint with theglass to prevent the passage of heat from one chamber to the next. This object is accomplished by the provision of the asbestos sheets 18 clamped at their lower edges between the pairs of asbestos plates 19, which latter plates fit loosely over the upper edge of the plate 16; The lost motion connection between the plates 18 and the diaphragmwalls 14 is necessary in order to permit the passage of aV sheet of varying thickness and also to permit the passage of the bait employed for initiatingtheopela tion. In order to spread the plates 18 apart before the baitarrives, separator devices 20, carried at the side walls of the leer casing upon vertically movable rods 21, may be employed. These rods are moved vertically to cause the members 2O` to engage the plates L18 and separate them by means of thelever 22 shown in Fig. 2 and havingk its end23 connected to the upper end of one of the rods 21.

VThe leercasing is divided into lsections which are independently supported from the surrounding framework in order to take care ofthe expansion and contraction ofthe casing, which would tend to buckle it and interfere with thek operation -of the roller mechanism carried inthe casing.' The sections are therefore hung from the sets of main transverse channels 2-2-2 with` telescopic joints at the abutting endsof the v sections, one of such joints being shown at 24 in Fig. 3. As here shown,` the shell of the one casing member telescopes inside the shell of the member just below, so thatthe two ends are free to move relatively in a vertical direction.. With sections` as short as the ones usedhere, this relative movement is, of course, slight, and al tight joint isinsured by placing an asbestos packing 25 between the edges of the opposing angles 26 and 27, Such angles' being riveted tothe opposing ends of the two sections.

, heating ofthe hollow front and rear wallsV of the compartments 8, 9 and-10 and also of As shown in Fi 3, the front and back walls of each cham er, such as the chamber 7, are provided with hollow walls which give the spaces 28 and 29, and the outer Wall of thesek spaces is preferably provided, as indicated at Fig. '5, with an insulating coat ing 30 of asbestos. The. spaces 28 and 29. may be heated `with gas burners extending through the openings 31, the upper openings 32 serving .s exits for the gases of combustion. The temperature of each of the chambers or compartments 5 tov 13 may in this way beregulated so as to give the gradually decreasing temperature from the lower to the upper end of the leer in order to provide for annealingthe glass and for rebers comprises a shaft upon which are mounted a plurality of rolls, each of which is supported iexibly so that the roll members may adjust themselves to inequalities of the sheet and avoid imposing a crushing strain in case the sheet should be warped or of uneven thickness. This construction is ,shown in detail in Figs. 4 and 5, which will ducing it to a temperature at which it is safe to bring it into the outer air and cut it ott. Additional temperature controlling means are also provided upon the. side walls of the leer casing. As indicated in Fig. 3, in conjunction with Figs. 4.and 5, hollow walls are also provided upon these sides of the leer casing, giving the chambers 33 and 34. A gas and air mixer discharges into theopening 35 at the lower corner of the cham er 33, and the Vgases of combustin arek carried transversely through this chamber 33 to the outlet 36at wh'ch point a pipe 37 carries the hot gases tothe inlet 38 ol the chamber 34. From this point the gases pass to the outlet 39 of the chamber 34 and thencek upward through the pipe 40 to an' inlet opening in the next heating chamber correspondingv in position to the inlet open'- ing 35.` The gases of combustion aren this way carried up through the heating chamber on the sides of the three'v compartments 5, 6 and-7, afterwhich they'are discharged. Aj similar arrangement provides' for the the walls of the compartments 11, 12 and 13.

-In this way the heating of the chamber and the regulation of the temperature inside the cas'ngl 'supplements the regulation of the heating secured from the sets of chambersV 28 and 29 at the front and rear of the casing heretofore referred to, and thetemperature of the glass is controlled from the time it enters the leer until it passes out at the upper end, suitable pyrometers .and vautomatic regulating devices ybeing used if des sred, to give the desired temperature in each of theJ compartments 5 to 13. v In order to permit of the removal of broken glassy from the compartments and to give access to the interior of the .construction for other purposes, the portions of the walls marked 41 in Fi 3 are made of single thickness instead 0% being made ho'llow, and are bolted removably in position. f

" `In each of the compartments of the, leer are a pair of vroll members for advancing 'the sheet of'glass.l Each of these roll membe readily understood hy reference thereto in connection with Fig. 3, and it will be understood that these roll constructions are the same in all of the compartments so that a description of one will be suflicient for all. This roll construction constitutes lan improvement on the construction shown and claimed in my Patent No. 832,860 of November 21st, 1905. As indicated in Fig. 5 in connection with Fig. 43, the opposing sets of rolls 42 and 43 are mounted upon thel shafts 44 and 45, the shafts themselves being journaled at their ends in the upper ends of the levers 46`and 47. Lying immediately below 'the shafts 44 and 45 in vertical alignment therewith are what may be called the supportingshafts 48 and 49 (Fig. 4), and the levers 46 and 47 which carry the roll shafts 44 and 45, are pivoted upon these supporting shafts. are mounted inbearings 50, 51and 52 located outslde of the leer compartment (Fig. 4) and.l supported upon transverse frame members 53, 54 and 55, which constitute a part of the framework surrounding the leer casing. The roll shafts are pressed yieldingly toward'each other bythe-springs 56 and 57 (Fig. 3) mounted upon the shaft 58 and being regulated as to compression vby means of the nuts 59. The movements of the rolls away from' the center line 604 of the leer are. made equal by the use ofthe levers 46 and 47, sothat the-movement of "one roll outward from the center line 60 causes the other roll to move out an equal distance.

The supporting shafts Fumble mounting of therous 42 and 43 upon the shafts 44 and 45 is accomplished as indicated in Fig. 4, a collar 62 keyed to the shaft 44 being provided intermediate each pair of rolls. VThis collar carries three transverse rods 65 mounted for universal mov'e-.

ment in the collar as indicated at 66. These shafts carry at their ends the ball members 67 mounted for universal movement in the hubs of the rolls `as indicated in Fig. 4. This ar,- rangement provides for the adj ustment'ofthe rolls to any inequalities of the sheet to prevent breakageedue to such inequalities. In order to lgive these rolls a yieldingly refractory surface, which will notmar the glass and which willbe serviceable throughout a ylong continued period of use, a wrapping of asbestos cord is provided as shown 1n detail in Figs.v 6 and-7. This cord is wrapped cir cumferentially of theroll and comprises, a central wire of copper or composition 68 surrounded by, a woven fabric of asbestos, each strand of which has a core 69 of wire. This fabric is wovenor braided around the wire with what is known asthe may-pole weave or braid, the threads of thel fabric intermeshing as" indicated in Fig.U 6. Thisconstruction gives a Tuilley coating which-is eX- ceedingly resistant to `wear'as the weave of small wiresthrough the fabric tends to hold the fabric together and give it the necessary tensile strength. The wire in the center gives the vcord the additional reinforcement necessary to prevent itfrom being broken under strain, and clamp it to the drum.

The supportin shafts 48 and 49 serve to maintain the rrol s on oppositesidesof the sheet in the same horizontal alignment, so that pressure is applied upon the lsheet. on lines which are in the same horizontal plane, thus avoiding any breakage suchas might occury where flexibly mounted rolls are employed, in which the horizontal center lines werev capable o'f being thrown out of alignment during the drawing operation. These supporting shafts are provided with collars 70, which engagethe metal off the rolls outside the asbestos winding.l The'supporting shafts are preferably driven so that the collars 70 have the same peripheral speed as that of the rolls 42, so that there'is no retarding eii'ect incident to the employment of the supporting rolls. ,The driving connection between the roll shafts and supporting rolls is secure-d by means of the gear 71.0n the rollshafts which engage pinion 72 on the supporting shafts..4 The outer ends of the -supporting shafts 48 and 49 are driven by means of the sprocket' wheels 73 and 74, whose opposing toothed flanges overlapand engage the driving sprocket chain 75, as indicated in Figs. 3 and 5.- The driving sprocket chain 75l is arranged as shown in Fig. 2 and lextends in a vertical planefro'm the bottom of theleer casing to the top, ypassing' betweenall the sets ofsprocket wheels73 and 74.- After passing the set of sprocket wheels-for the compartment 13, the chain passes over "the idler sprockets 7 5a and 7 6. the latter being yieldingly supported in the bearing member 77,

.whose shaft isv threaded for adjustment through the nut Y7 8 'and is yieldingly supported by the coil spring7 9. The chain extends downward from the sprocket 76 to the lower end of the casing, where it passes around vthe pair of sprockets 80 and 81, the

latter sprocket being mounted upon a'counter shaft 82, which is driven by a chain 83 passing around the sprocket on the shaft 84 of themotor 85. The roll shafts are in this manner all driven, at a'constant speed and 'effect a, drawing of the glass by means ofthe flexibly mounted rolls which are yieldingly pressed against theglass with a` force which y may'beadjusted :to suit conditions andfwliich will Veffect the ,drawing 4of they glassfeven to warping and varying thickness.

As theglass cools more rapidly `at its edges than in the intermediate portion` in though the sheet is somewhatout of true, due

.passingfrom the'bathto the leer, it ris desirable tosapply more heat to vsuch edges than at the central portion of thejsheet after it enters lthe leer. The walls` of the leer opposite the edges ofthe sheet are therefore more hi hly heated than.the walls opposite vthe si es' in the lower portion ofthe leer. As

the sheet progresses upwardly it gradually ,80

'length of thecasing dividingk itinto a plurality of compartments", and yheatingnieans for the hollow' walls of each compartment so that the temperature ofthe various ,compartments may be independently regulated. y

y2. In combination in a leer for' annealing a glass sheet drawn continuously from a molten bath, a yvertical leer casing having hollow walls, drawing means'arranged along thelen'gth of the 'casing `for engaging the glass and advancingji't therethrough, 'transverse partitions arranged at intervals along the lengthof the casing dividing itinto a plurality rof compartments, the said partitions having slots to permit `.the passage of the glass sheet, and sheets lof woven rethe clearance 1 fractory material for, closin spaces between the edges'fo y'the partitions at the slots Vand the glass.

i 3. In combination in a leer for annealing a glass sheet drawn continuously` from a molten bath,a vertical leerf casing havin i hollow walls, drawingV means arrange along the length of the casing for engaging the glass and advancing it therethrough, transverse partitions arranged at intervals along the length of the casing dividing it into va plurality of compartments, the said partitions having slots to permitthe passage of the" glass sheet, and yleldinggrefractory means carried by the partitionsat the slotsy and engaging the glass sheetfor closin Vthe clearance spaces betweenthe edges oy the slots and the sides of the glass sheet.'

s 4. In .combination vin aleer for annealing a Vglass sheet Vdrawn *continuously/ from: a molten bath, kaf verticalv leer leasing havin hollow 'wal1s,'V drawing means arrange l along thelength of thecasingv for engaging the glass and .advancing it therethrough,

`transverse partitionsy arranged atintervals along lthe length of thecasing` dividing it into a plurality of compartments, the said partitions having vslots topermitthe passage `of the glass sheet, and inclined yielding sheets of asbestoscarriedby the partitionsandadapted toengage the glass sheet.

- 5. In combination in a leer for kannealing a glass vsheetfdraivn continuously from a molten bath, a vertical leer casing'having hollow walls, -drawing 'means arranged alongpthe length of the casingl for engaging the glass` and advancing; it therethrough, transverse partitions arranged `at intervals along the length of the casing dividing it into a plurality of compartments, the said partitions having slots to permitthe passage of the glass sheet, and 'yielding means carried by the partitions rat the slots and engaging the glasssheet for closing the clear- 'ance spaces between the edges of the slots and the sides of the glass sheet, said yielding means being mounted 'with lost motion 6. In combination in a connections to permit of the passage of a leci` for annealing V continuously'formed sheet'glass, a vertical framework, an annealing casingrextending vertically upward inside'` said framework and comprising a series of aligned sections in telescopic relation, and means for supporting the sections independently from the framework' n 7. In combination in'aleer for annealing continuously formed sheet glass, a vertical framework, an annealing casing vextending ,e vertically upward' inside said framework and comprising a series of aligned sections in telescopic relation, packing means at the joints between thesections', and means for supporting the sections independently from 8. In combination in af leer for annealing continuously "formed sheet glass, a vertical framework,`an annealing casing extending vertically upward inside said framework and comprising a series of aligned sections having their adjacent ends relatively movable, and means for supporting the sections independently from` the framework i 9. 'Incombination in a leer for annealing continuously formed ksheet glass, a vertical framework, an annealing casing 'extending vertically upward inside said framework and comprlsing a series of aligned sections having their'adjacent ends relatively movable, glass'advancingmeans foreach section, and means for supporting'eachsection and its advancing means from the 'frame- Work independent of eachother-section and its advancing means.

t 10:- In combination ina leer for annealing continuously formed sheet glass, a leer castoothed driving sprockets for each pair of rolls, having their toothed peripheries overlapping. anda chain for driving said sprockets, said chain extending between each pair of sprockets and engaging both sets of overlapping `teeth on the opposing sprockets 11'. ln combination in a leer for annealing continuously formed sheet glass, la leer casing, a pairof opposing roll shafts extending across the casing, a plurality of rolls flexibly` mounted on each shaft to permit the rollsV to coliforml themselves to the contour of the glass sheet which is being drawn, and a supporting shaft lying beneath eachy of the rollshafts and in engagement with the peripheries'of the rolls upon such shafts.

12. yIn combinationin a leerv for annealing continuously formed sheet glass, a leer easing, a pair of opposing roll shafts extending across the casing, Va plurality of rolls flexibly mounted on veach shaft to permit the rolls to conform themselves to the contour of the glass sheet which is being drawn, a supporting shaft lying beneath each of the roll shafts and in engagement with the peripheries of the rolls upon such roll shafts, 1

and means for driving the supporting shafts.

13. In combination in a leer for annealing continuously formed sheet glass, a leer casing, a pair of opposing roll shafts extending across the casing, a plurality of rolls flexibly mounted on each shaftto permitthe rolls to conform themselves to the contour of the glass sheet which is being drawn, a supporting shaft lying beneath each of the roll shafts and in engagement with the peripheries of the rolls upon such roll shafts, and means for driving the supporting shafts at approximately the same peripheral speed as that of the rolls.

14. Incombination in a leer for annealing continuously formed sheet glass, a leer casing,

a pair of opposing driven roll shafts extending across the casing and mounted for movenient-toward and from each other, a plurality of rolls flexibly mounted on each shaft to permitthe rolls to follow the contour of the glass passing the` rolls, a supporting shaft lyingbeneath each ofthe roll shafts andy in engagement with the peripheries of the rolls upon such roll shafts, and means for driving `the supporting shafts. v

15. In combination in a leer for annealing continuously formed sheet glass, a leer casing, a pair of opposing4 driven roll'shafts extending across the casing, a plurality of rollsy flexibly mounted on leach shaft, a supporting shaft lying beneath each of the roll shafts and in engagement with the peripheries of the rolls upon such roll shafts, bearings for the supporting shafts, lever arms in which the roll 'shaftsl are pivoted and which are themselves pivoted on the supporting shafts, gear connections between the roll shafts and supporting shafts, and a link connection between the lever arms.

16. In combination in a leer for annealing continuouslyformed sheet glass, a leer casing, a pair of opposing driven roll shafts eX- tending across the casing, a plurality of rolls flexibly mounted on each shaft, asupporting shaft lying beneath each of the roll shafts and in engagement with the peripheries of the rolls upon such roll shafts, bearings for the supporting shafts, lever arms in which the roll shafts are pivoted and which are themselves pivoted on the supporting shafts, gear connections between the roll shafts and supporting shafts, a link connection between the lever arms, and means for rotating the supporting shafts.

17. In combination in a roll for use with sheet glass, a metal pulley and an asbestos cord facing wound on the periphery of the pulley, the said cord comprising a central wire with an asbestos fabric woven around it, and the strands of asbestos fabric having wire centers.

18. In combination in a roll for use with sheet glass, a metal pulley and an asbestos cord facing wound on the periphery of the pulley, the said cord comprising a central wire with an asbestos fabric woven around it in an intermeshing braided form and the strands of asbestos fabric having reinforcing centers of fine wire.

19. In combination in a leer for annealing a glass sheet drawn from a molten bath, a vertical casing, drawing means for advancing the glass through the casing, partitions dividing the casing into a plurality of compartments and means for heating the walls of the compartments at different levels independently to control the cooling of the sheet as it is drawn.

20. In combination in a leer for annealing a glass sheet drawn from a molten bath, a vertical casing divided into a plurality of compartments one above the other drawing means for advancing the sheet through the casing, means for heating the walls of the compartments opposite the sides of the sheet and other means for heating the Walls of the compartments opposite the edges of the sheet.

21. In combination in a leer for annealing a glass sheet drawn from a molten bath, a

vertical casing divided into a plurality of compartments one above the other drawing means for advancing the sheet through the casing, means for heating the walls of the compartments opposite the sides of the sheet and other means for heating the Walls of the compartments opposite the edges of the sheet, the said heating means being arranged to give a gradually decreasing temperature in the compartments from the bottom up.

22. In combination in anl apparatus for annealing a glass sheet drawn from a molten bath, a vertical annealing leer above the bath having a series of temperatures in the succeeding portions thereat, gradually decreasing from the bottom upward, and a plurality of vertically spaced heating means for controlling and regulating the cooling of the edges of the sheet by varying the temperature of the leer opposite the edges of the sheet.

23. In combination in a roll for use with sheet glass, a metal pulley, and an asbestos cord facing wound on the periphery, the said cord comprising a central wire with an asbestos fabric woven around it.

24. A process for annealing a sheet of glass drawn upward from a glass bath through an annealing leer which consists in first passing the sheet through a section in the leer in which a higher degree of' heat is applied to the edges of the sheet than to the intermediate portion, to bring the sheet to a uniform temperature, and then passing it through a section in which the degree of heat applied to the edges is the same as that applied to the sides of the sheet, the de ee o heat applied to the sheet being gradualy decreased as the sheet progresses upwardly through the leer.

In testimony whereof, I have hereunto subscribed my name this 30th day of July, 1921.

HALBERT K. HITCHCOCK. 

